Apparatus for making sheet glass



APPARATUS Sept. y'7 1926.

W. G. KOUPAL ET AL Sept. `'.7' 1926.,

APPARATUS FOR MAKING SHEET GLASS Filed Jan. 13, 1926 3 Sheets-Sheet 2INVENTOR Sept. 7 1926. 1,598,729

W. G. KOUPAL. ET AL APPARATUS FUR MAKING SHEET GLASS Fil-ed Jan. 13,1926 3 Sheets-Sheet 5 INVENTOFZ Patented Sept. 7,. 192.@

UNITED, sfr/.irlasy 1,598,129 PATENT" OFFICE'.

WALTER. G. Korir-u. AND JOSEPH. S. GREGQRIUSJ or nevarvanNoN,f'n1o',-'As.

SIGNQRS fr0 211175131111@ PLATE, GLASS, comma-Y, A Couronnes@ PENNSYL-Armentieres meme .SH-aar; Gruss.

Applicaties filed Jennery The invention relates to apparatus for makingsheet glass and particularly to the drawing tank construction. vIt Ahasforfits principal objects the provision of anl im-,. proved arrangementof the clay work over the bath,' designed so as` to. secure a vreduction of the temperature art-the central por. tion of the bath ascompared with that at the side portions. The glass bath at its cen. tralportion normallyhas asomewhat higher temperaturev than the'sideportionaldue to the greater dissipation of heat at the sides of the bath incidentto the conductingeffect of the side walls of the tank. This tends togive a sheetJ which is hotter the center and;

detail rear elevation of one of the L-blocks' and a vertical section ontheline IV-I`V of Fig. 3 respectively. And Figs. 5 and 6. and 7 and 8are detail views of L-blocks showingr modifications` Fig. 6 being aseotion on the line VI-VI of Fig. 5 and Fig. 8 being a section on theline VH1-VIH of F ig. '7.

Referring to the general arrangement of F ig. 1, the reference numeral 1indicates the end ot a glass melting tank preferably of the regeneratortype and 2 is a forehearth or drawing tank leading from the end of themelting tank. A gate 3 of refractory material is employed for partiallysegregating the glass in the tank 1 from that in the tank 2. A cover forthe tank 1 is provided in the formy ol the hloclrs land 5 spaced ahovethe surface of the glass, and between .these blocks is a drawing openingthrough which the sheet 6 is drawn upwardly through a leer 7. Anydesired form of drawing means may be employed, the one illustrated beinga. series of pairs of rolls 8 mounted in the leer 7 and engaging thesides of the sheet7 this being; a well-known 1a, 192e.Y serial Np.59,947.

means for dravving glass vertically. *i At the edges of the sheet are`the edge holding' devicesfQ, preferably of the type shown 1n theSlinglu'l Patent "No,r 1,549,513 of August .11,y 192555v and 'beneaththe liney of generation of the sheet is a refractory.draw-bar.10. Theedge. holding devices and the draw-bar are details ofconst;ruction'Which have nothing todo `with the present invention, butare illustrated `for the purpose of showingl a complete.'installation r0n eachfiside of' the sheet isan L-block 11.' each of' which hasl akvertical flange 12 and a horizontal portion 1,3.V The flange 12 isbowed down at its centergasl indicated in Figs. 2 and 3,` so. that it iscloser to the sur-v face ont' the hath at the center than at the edges.'The horizontal portion, 13, on the other hand. is arched upwardly atitscentrail portion. as indicated at 14 in Figs. 2 and 3, so that theface ol the arch is more remote from the surface of the glass at itscenter than at its` edges. y

As heretofore indicated., the L-block construction is designed to reducethe temperature of the glass at the center of the bath as compared withits edges. The bowing down ot' the flange 12 tends to produce thisresult.v as does also the arch inthe reverse direction of the horizontalportion 13 of vthe block. The spaces 15 andy 16 back of the L-hlocks andlying. between the surface of the glass and the blocks 4; and 5 areheated byvsuitahle burners working through the openings 17 and 18a.. andthe hot ,eases conthanat their center portions and .the heating' effect.ot these gases is. therefore, greater at the sides of the bath than atthe center. As a result, this arrangement has a tendency to, @quali/.ethe temperaturefof thesurface glass from one side of the bath to theother` as such glass is normally at a somewhat lower temperatureladjacent the side Walls ot the tank than at the central por- 'loo sa,AA

tion of the bath. The arch arrangement of the horizontal portions 13,'13tend to give a greater heating effect at the sides of the bath thanat the center, as the intensity of the heat reflected from the cla'vwalls 13, 13 decreases with the distance from the bath, and theabsorption of heat by the air lying between the walls 13 and thebatlifisgreater at the center where the layer of air has the greatest thickness.The constructionof the fiange 12 and the arch 13, therefore` cooper'-ates toiequalize the temperature of the glass from one yside of the bathto the other, so that the glass is no hotter atA the center of the bath'than at'the edges and as' a result,

the glass sheet of uniform thickness is produced. The modifying effectof the L-blocks upon the glass may be adjusted by raising and loweringthem so as to secure the same temperature condition on both sides of thesheet.

Suitable water coolers 17 and 18 are also preferably employed on eachside of the sheet, such devices serving to chill tlieglass bath byabsorbing heat therefrom, this detail of construction also being onewhich is well-known in the art and constitutes no part ofthe presentinvention.

Figs. 5 and 6 show a modification in which the L-block 19 has its lowersurface 20 bowed, as indicated in. Fig. 5, the arch arrangement of theFig. 1 construction being omitted in this modification, and the blowingv down of the block being entirely ldepended upon to secure thenecessary modification of temperature in the glass bath. Figs. 7 and 8illustrate a further modiiication in which-the flange. 21 of the L-block22 has its lower edge straight,fas yindicated in Fig. 7. With thisblock, the horizontal portion 23 is arched as in the Fig. 1construction, this arching being relied upon to givel the desiredtemperature modification. From the modifications it is apparent that thetwo features of bowing a part of the block down and archinganotherportion of the block may be employed separately, if desired.; themost,effective result, however, being secured when both of these features areused in the same L-block.

. What we claim is: y

1. The combination with a glass tank',

.having a refractory top spaced above the f glass with a drawing openintherethrough and sheet drawing means or `drawing a sheet upward fromthebath with its line of generation lying transversely of the tank, of arefractory block extending transversely of the tank on each side of thedrawing opening and having its lower edge extending down below said topto a level adjacent the surface` ofthe glass bath in the tank, the saidbottom edge of eachblock being bowed down so that it is closer to thebath at the central portion thereof than at the edges.

2. The combination with a glass tank, havingja refractory 'top spacedabove the glass with a drawing opening therethrough and sheet drawingmeans for drawing a sheet upward from the bath with its line ofgeneration lying transversely of the tank, of a refractory blockextending transversely of the tank on each side of ,the drawing openingand having its lower edge extending down below said top to a leveladjacent the surface of the glass bath in the tank` the portion of eachblock on the side toward the sheet E having its lower surface cut awayaboifelthelevel of said bottom edgeV so as to forman archwhichapproaches the bath from its' vcentral portion to its side portions.

3. The combination with `a glass tank,

having a refractory topspaced above the glass with a drawing openingtherethrough and sheet drawing means for drawing a sli-eet upward fromthe bath with its line of generation lying transversely of the tank, ofa refractory block extending transversely of the tank on each side ofthe drawing opening and having its lower edge extending down below saidtop to a level adjacent the surface of the lass bath in the tank, thesaid bottom edge o each block being bowed down so that it is closer tothe bath at the central portion thereof than at the edges, and theportion of each block on the side toward the sheet having its lowersurface cut away above the level of said bottom edge so as to form anarch which approaches the bath fromits central portion to its sideportions.

gthThe combination with a glass tank, having a refractory top spacedabove the glass with a drawing'opening therethrough and sheet drawingmeans for drawing a sheet' upward from the bath with its line ofgeneration lying transversely of the tank, of a refractory block L-shapein cross section extending transversely of the tank on one side of thedrawing opening and having a vertical fiange at its bottom portion2extending down adjacent the surface of the glass bath in lthe tank, thelower face of said block on the side of the sheet toward the drawingopening being arched so that such lower face at its central portion isfarther from the glass bath than at its sides.

In testimony whereof, we have hereunto subscribed our naines this -8thday of J anuary, 1926.

WALTER G. KOUPAL. JOSEPH S. GREGORIUS.

